* {
    margin: 0;
    padding: 0;
}

body {
    background-repeat: no-repeat;
    background-attachment: fixed;
    background-size: cover;
    background-image: url(https://img.xjh.me/random_img.php?type=bg&ctype=nature&return=302);
    /* ctype 的值为 nature 时为获取环境背景图，值为 acg 时为获取人物背景图 */
}

a {
    text-decoration: none;
    /*去除超链接的下划线*/
    color: #19f;
}

input {
    border: none;
}

div {
    display: block;
}

.container {
    position: absolute;
    top: 50%;
    left: 50%;
    margin: -175px 0 0 -370px;
    width: 740px;
    height: 350px;
    border: 1px solid #aaa;
    border-radius: 20px;
    background-color: #fff;
}

.top {
    display: flex;
    height: 295px;
    margin-top: 34px;
}

@media only screen and (min-width: 741px) {
    #main {
        width: 65%;
    }
}

@media only screen and (max-width: 740px) {
    .container {
        margin: -300px 0 0 -200px;
        width: 400px;
        height: 600px;
    }

    .top {
        display: flex;
        height: 545px;
        margin-top: 34px;
        flex-direction: column;
        align-items: center;
    }

    #main {
        margin-top: 25px;
        width: 100%;
    }

    .main_0 form .user input {
        width: 225px;
    }

    .main_0 form .pass input {
        width: 155px;
    }

    .main_1 form .user input {
        width: 211px;
    }

    .main_1 form .pass input {
        width: 135px;
    }

    .pass_on {
        top: 400px;
        left: 110px;
    }
}

#main {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-left: 17.5%;
    align-self: center;
}

.main_0 .or .left,
.main_1 .or .right {
    color: #19f;
}

.or .left,
.or .right {
    cursor: pointer;
}

.or * {
    font-size: 20px;
    font-weight: 530;
}

.on_l {
    background-color: #eee;
    border: 1px solid #aaa;
}

.on_r {
    color: #fff;
    background-color: rgb(43, 148, 213);
    border: 1px solid rgb(43, 148, 213);
}

#main form {
    margin: 25px 25px 10px 25px;
    width: 80%;
    font-size: 14px;
    display: block;
}

#main form .user {
    height: 35px;
    border: 1px solid #aaa;
    border-bottom: none;
    border-radius: 10px 10px 0 0;
    line-height: 35px;
}

#main form div span {
    margin: 0 20px;
}

#main form div input {
    height: 30px;
}

.main_0 form .user input {
    width: 306px;
}

.main_0 form .pass input {
    width: 236px;
}

.main_1 form .user input {
    width: 292px;
}

.main_1 form .pass input {
    width: 216px;
}

#main form .pass {
    margin-top: -1px;
    height: 35px;
    border: 1px solid #aaa;
    border-radius: 0px 0px 10px 10px;
    line-height: 35px;
}

#main form div span {
    margin: 0 20px;
}

#main form div input {
    height: 30px;
}

.main_0 #pass_b,
.main_1 #pass_a {
    display: none;
}

#pass_b {
    cursor: pointer;
}

.on {
    display: flex;
    justify-content: center;
    flex-direction: row-reverse;
}

.qita {
    font-size: 15px;
    color: #aaa;
}

.list {
    margin-top: 12px;
    width: 80%;
    display: flex;
    justify-content: space-evenly;
}

.list a {
    display: flex;
    line-height: 30px;
    color: #000;
    font-size: 14px;
}

.weixin {
    background-image: url(../img/weixin.png);
}

.weibo {
    background-image: url(../img/weibo.png);
}

.qq {
    background-image: url(../img/qq.png);
}

.on {
    display: flex;
    justify-content: center;
    flex-direction: row-reverse;
}

.on_r {
    color: #fff;
    background-color: rgb(43, 148, 213);
    border: 1px solid rgb(43, 148, 213);
}

.on * {
    margin: 3%;
    width: 43%;
    height: 35px;
    border-radius: 10px;
    line-height: 35px;
    text-align: center;
    cursor: pointer;
}

.on_l {
    background-color: #eee;
    border: 1px solid #aaa;
}

.pass_off {
    display: none;
}

.pass_on {
    position: absolute;
    /*使子元素按父元素的位置进行定位*/
    top: 150px;
    left: 440px;
    width: 250px;
    height: 140px;
    background-color: #fff;
}

.pass_on a {
    padding-left: 5%;
    line-height: 195%;
    display: block;
    width: 95%;
    height: 50%;
    border: 2px solid #aaa;
}

.bottom {
    display: flex;
    flex-direction: column;
    font-size: 10px;
    color: #aaa;
    align-items: center;
}